The present invention relates to a charging apparatus suitable for charging a battery pack used as a power supply of an electronic equipment such as a camera integrated video tape recorder (hereinafter referred to as a video camera), a portable telephone and a personal computer.
Hitherto, a battery pack composed of a secondary battery such as a lithium ion cell, a NiCd cell and a nickel hydrogen cell has been used as a power supply of an electronic equipment such as a video camera, a portable telephone and a personal computer.
Various charging apparatuses for charging a battery cell of such battery pack have been also proposed since the past. As a charging apparatus which is arranged so as to indicate charged capacity of the battery cell being charged, there has been one which discriminates and indicates whether or not the charged capacity of the battery cell has reached 90%.
However, such conventional charging apparatus has had a problem that its user is unable to know the charging state in detail because it gives no indication about percentage how far the battery cell being charged has been charged.
It also has had a problem that the user is unable to know the degree of charge, i.e., how far the battery cell has been charged, which enables an electronic equipment, e.g., a video camera, using the battery pack to be driven for how many hours at the present point of time of the charge and that electricity cannot be charged in a planned manner only for the shooting duration necessary for the user, thus taking a time for charging unnecessarily.
Although there has been a method of stopping to charge the battery cell of the battery pack on the way and of attaching the battery pack actually to an electronic equipment, e.g., a video camera, and turning on the power supply to confirm the remaining usable duration and the capacity of the battery cell, it has had a problem that it is cumbersome and is inconvenient for the user.